LAN is always most fun.
online just irritates me and you don't have the presents of your fellow friends in another room. plus, pizza!
Xbox online is better than PS3 because im in a party, not hearing other people's BS. and get to talk to friends playing other games! AMAZING.
I would talk more but that's another topic. :P
LAN is preferred

heh, i actively had LAN parties throughout high school and they were pretty awesome. Used to play Generals, battlefield 2 and 1942 mostly. We still have one yearly LAN party around the end of the year. Even with wives and g/f, it is the one tradition my friend's and I keep alive. What makes LAN parties pretty awesome is having the people in the same room. While online can be fun, having people in the same room does make a very big difference. Never did the whole xbox LAN or what not, only did the PC LAN parties. I remember setting up the network in those days was usually the hardest part. Good ol' days.

I used to lan A LOT as a kid, warcraft III, age of empires II, battlefield II, age of mythology, you name it. Then in highschool I used to lan call of duty and halo about once a week with friends. Now I'm pretty into dota2 and with 4 other friends we have a team, so while we mic chat a lot, we still try to lan when we can. Lan is definitely better, hands down, the fun factor is immeasurable, there's pizza, doritos, cola and chocolate, and you just get even more pumped during game. Now that we have cars we even go out a have a break while we eat, or if we had a bad game we can drive somewhere and chill out. Even if you play competitively I feel like lan's are better since it forces people to get over their emotional problems and focus on the game.

Ahh, LAN is always better, being in the same room, you can slug someone for killing you. Makes me nostalgic for the days I'd go over to my cousin's place to play GoldenEye on N64. Also less network issues such as lag.